Block construction for boiler tubes and the like



J. E. BIERY March 10, 1936.

BLOCK CONSTRUCTION FOR BOILER TUBES AND THE LIKE Filed July 14, 1931 Lb ATTORNEY v Patented Mar. 10, 1936 UNI-TED STATES BLOCK CONSTRUCTION FOR BOILER- TUBES AND THE LIKE John Edward Biery, Grantwood, N. J., assignor to Foster Wheeler Corporation, New York. N. Y., a corporation of New York Application July 14, 1931, Serial No. 550,677

6 Claims.

My invention relates to armor or refractory coverings for heat absorbing members such as water tubes of water tube boilers.

One object of the invention is to provide a sim- 5 'plified construction of multiple-piece adjustable armor block units. Another object is to provide an armor construction permitting wide variations between centers of tubes and wide variations in tube alignment. Still another object is m to provide armor construction of the type referred to applicable to straight or curved tubes.

Further objects and the nature and advantages of the invention will become apparent as the description proceeds.

15 On the accompanying drawing, I have shown one embodiment of the invention by way of illustration but it will-be understood that the invention is not limited to the particular structure illustrated.

20 Referring to the drawing, which is to be considered as a part of this specification;

Fig. 1 is a cross-sectional view of a water wall embodying my invention and is taken on the line I-I of Fig. 2;

5 Fig. 2 is a cross-sectional view taken on the line 2-2 of Fig. 1 and on the line 22 of Fig. 3;

Fig. 3 is a cross-sectional View taken on the line 33 of Fig. 2; and

Fig. 4 is a perspective view of a block made 30" in accordance with my invention.

Reference character III designates generally a water wall of a furnace or the like. Water wall I comprises a plurality of spaced tubes I I which may be connected to a common drum I2. Drum 35 I2 may be located outside of the furnace and tubes II pass through furnace wall I3. The portions of tubes II inside the furnace wall are provided with an armor I4 made of blocks of cast iron or other suitable refractory material. The

40 space behind tubes II is ordinarily filled with a plastic refractory material I5 held in place by means of sheet metal or the like.

Armor I4 comprises block units I8. Each block unit in turn comprises a pair of refrac- 45 tory block members I9 and 26. Block members I9 and 20 are of identical form and have a rectangular front fire surface or face 2| and cylindrical tube receiving recesses 22 providing surfaces for contact with the tubes. The side or 50 wall I! of each block member opposite from tube receiving recesses 22 is preferably a plane surface and has a wedge-shaped recess 23- therein. One wall or surface 24 of this recess is inclined with respect to other walls of the block 55 and is preferably fiat. The width of the recess 23 is substantially less than the width of the wall IT in consequence of which the fire surface or face 2| is continuous and the wedging means hereinafter referred to is not exposed to the heat of the combustion gases or flame. A semi-circu- 5 lar groove 25 extends from the rear face of the block into recess 23.

The two blocks I9 and 20, forming a block unit I8, are mounted forwardly on and between adjacent tubes with the side walls I1 and the recesses 23 of the respective blocks adjacent to each other as shown in Fig. 2. Before the blocks I9 and 20 are placed on the tubes a wedging member comprising a tapered head 26 and a shank 21 is placed between the blocks and in the recesses 23. The shank 21 extends through the opening formed by the grooves 25 in the block members.

i A rigid backing member 28 having circular tube receiving recesses I6 is mounted rearwardly on tubes II. Member 28 is provided with upper and lower flanges 29 between which extends a bridge portion or member 30. Bridge portion 38 is provided with an opening 3| which, when the rigid backing member is in place on the tubes, is in line with shank 21. Shank 21 is threaded at the end opposite to the tapered head, and the threaded portion extends through opening 3I and a nut 32 bearing against a washer 33 is threaded thereon.

When nut 32 is turned up it draws the wedgeshaped head 26 toward rigid backing member 28 and hence causes the wedge-shaped head to bear against the inclined walls 24 of the recesses 23 and hence to force blocks I9 and 20 apart 35 so that they are normally out of contact with each other. The side walls of the tapered head are preferably flat and are angularly disposed at the same angle as that between the adjacent walls 24 when the block members are mounted as shown in Fig. 2 with walls I! parallel. When the blocks are forced apart their tube receiving recesses 22 are forced in close contact with tubes II.

Rigid backing members 28 are also provided with flanges 34 at their ends. These flanges are formed with apertures 35 through which may be passed bolts 36. When all of the rigid backing members 28 in one row are secured together by means of bolts 36 there results a single rigid 5o backing member which extends the entire width of the water Wall. The advantage of this is that when the blocks I9 and 20 are forced against the tubes there is a tendency to spread the tubes and this rigid backing member resists this tendency. It is apparent that blocks l9 and 20 may be very readily secured to the tubes, requiring a minimum amount of time and labor. Moreover, these blocks are of a comparatively simple form and are cheap to cast.

My improved block unit is well adapted to be used on bent portions of the tubes, as at 31 or 38 on Fig. 1. For use under these conditions, the blocks are preferably made shorter thanfor use on the straight portions of the tubes. Also the tube receiving recesses 22 are made curved order to fit the bend in the pipe but no change is necessary in the rest of the block, including surface 2! and grooves 23.

My improved block unit and wedgingmeans is applicable to a variety of heat absorbing apparatuses and to tubes for heating water, steam, oil or other fluids. It is applicable to any system of blocks to form a substantially continuous surface where intimate contact is required, adjustment is necessary or desired and expansion strains are to be taken care of.

It will be noted that the block members are not intended to swing on the tubes nor to normally bear on or to normally contact with each other but are designed to have straight movement. Obviously the wedging surface may be somewhat curved if desired and some rolling on the tubes may take place. I prefer, however, to have the block units and wedging members so designed as to give a spreading of the blocks parallel to the plane of the centers of the tubes; that is so that the front fire surfaces 2-! are maintained'in a single plane. The blocks may be applied to other surfaces than tube surfaces and are readily adaptable to surfaces of various configurations.

The proportion of surface contact with the tube can consist of from 25 to 50% of the tube surface. The intimacy of contact is maintained regardless of temperature conditions. The greater the expansion, the greater the pressure against the tubes. It will be seen that the blocks can be adapted to the tubes even though the tubes are out of alignment and that they need not be used to force tubes to any given alignment. It will be readily seen that the application of blocks in accordance with the invention isparticularly advantageous to curved portions of tubes. This facilitates the application of blocks close to a header where tube holes vary, such as in certain chain grate stoker installations. The blocks can be applied in staggered arrangement, staggering each block to any desired angle.

While I have shown and described one embodiment of my invention for the purpose of illustration, it is to be understood that my invention may be embodied in a variety of other structures. Among other variations, it will be understood that the tapered head 26 may be a separate member pivoted to the pin or shank 21.

What I claim is:

1. The combination with spaced tubes, of a block unit mounted forwardly thereon and therebetween comprising two block members, said block members having continuous heat absorption faces and curved surfaces on oneside contacting said tubes and opposite adjacent sides be- :tween said tubes and normally out of contact with each other, said adjacent sides being recessed to provide rearwardly converging wedging surfaces, a rigid backing member mounted on and rearwardly of said tubes, and a wedging member comprising a shank, a tapered head mounted on one end of said shank having rearwardly converging side surfaces adapted to contact said wedging surfaces, the extent of the recesses being such that the head of the wedging member is protected by said heat absorption faces and adjusting means mounted on the other end of said shank adapted to exert pressure against said rigid member.

2. A block of the character set forth having a flat front heat absorption face, a substantially plane Wall at one side of saigl face having a recess providing a wedging surface at an angle to said wall, and cylindrically recessed at a rear corner remote from the recessed wall.

3. A block of the character set forth having a flat front heat absorption face, a substantially plane wall at one side of said face having a re cess providing a wedging surface at an angle to said wall, said wedging surfacebeing intersected by a groove, and cylindrically recessed at a rear corner remote from the recessed wall.

4. A block of the character set forth having a fiat front heat absorption face, a substantially plane wall at one side of said face having a recess disposed centrally of said wall and providing awedging surface at an acute angle to said wall, said wedging surface being intersected 'by a groove, and cylindrically recessed at a rear corner remote from the recessed wall.

5. A block of the character set forth having a continuous heat absorption face, .a wall at one side of the face having a recess providing a wedging surface disposed at an angle to the wall, and cylindrically recessed at a rear corner remote from the recessed wall.

6. A block of the character set forth having a continuous rectangular heat absorption face, a wall at one side of the face having a recess providing a wedging surface disposed at an angle to the wall, and cylindrically recessed at a rear corner remote from the recessed wall.

JOHN EDWARD BIERY 

